1、Designation:D2043 94(Reapproved 2007)An American National StandardStandard Test Method forSilver Tarnishing by Paper1This standard is issued under the fixed designation D2043;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year o
2、f last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the qualitative identification ofthe presence or absence of materials in paper that will tarnisho
3、r stain silver which comes in contact with the paper.This testmethod is chiefly intended for testing tissue papers that are indirect contact with silver.The test results indicate the type oftarnish or stain and the relative distribution of the materialscausing such tarnishing or staining.NOTE1The ma
4、in material in paper causing silver to tarnish or stain isreducible sulfur,which may be determined in accordance with TestMethod D984.1.2 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establi
5、sh appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D585 Practice for Sampling and Accepting a Single Lot ofPaper,Paperboard,Fiberboard,and Related ProductD984 Test Methods for Reducible Sulfur
6、in PaperD1193 Specification for Reagent Water3.Summary of Test Method3.1 A specimen of the sample is saturated with water andplaced between two polished silver plates.The specimen isallowed to dry in contact with the plates at a temperature of70C for at least 3 h.At the end of the drying period,the
7、platesare examined for evidence of tarnish or stain.3.2 Water repellent or parchmentized papers and metal-coated papers will require certain modifications of the testprocedure.In most cases,they may be tested without wettingthe test specimen and by prolonging the time in contact withthe silver to at
8、 least 24 h.3.3 The principles involved in this test method are alsosuggested for use where wrapping paper is to be tested for itsstaining or corrosion properties with respect to other metals,such as steel,copper,nickel,etc.In such cases,plates or formsof the particular metal or alloy in question sh
9、all be used inplace of silver plates.Other modifications may be required fora specific purpose.For example,in the case of a metal thatwould rust,such as steel,the paper obviously could not bewetted;it would be necessary instead to heat in an atmosphereof high humidity.3.4 Modifications to accommodat
10、e paperboard are alsopossible.One such modification is described in the Appendix.4.Significance and Use4.1 This test method covers the determination of the pres-ence or absence of materials that will tarnish or stain silver inpaper used for wrapping silverware.Freedom from tarnishingsilver is an imp
11、ortant end user requirement of such papers.4.2 Possible modifications to other metals have specializedapplications in metal plating,graphic arts,and related areas.5.Apparatus5.1 Metal Surface,3solid silver or silver plated brass flatplates,approximately 15 by 15 cm(6 by 6 in.).Two plates areneeded f
12、or each test and are probably sufficient for occasionaltests of paper.Several sets are necessary where frequent testingis desired.5.1.1 Solid Silver Plates,approximately 15 by 15 cm(6 by6 in.).5.1.2 Metal PlatesFlat plates approximately 15 by 15 cm(6 by 6 in.)from commercial rolled sheet brass 0.25
13、in.(6.35mm)thick.One face of each plate should be buffed smooth andas free as possible from tool marks,then plated with pure silverto a thickness of about 0.125 mm,buffed again,and plated withanother 0.125 mm of silver.In this way,a smooth continuouslayer of pure silver about 0.25 mm thick will be o
14、btained thatcan be cleaned and polished repeatedly.It is advisable to check1This test method is under the jurisdiction of ASTM Committee D06 on Paperand Paper Products and is the direct responsibility of Subcommittee D06.92 onStandard Documents Relating to Paper and Paper Products.Current edition ap
15、proved April 1,2007.Published May 2007.Originallyapproved in 1964.Last previous edition approved in 2002 as D2043 94(2002).DOI:10.1520/D2043-94R07.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards vo
16、lume information,refer to the standards Document Summary page onthe ASTM website.3The metal surface required is not a stock item in many laboratory supplyorganizations,however the solid silver plates in 5.1.1 may be obtained upon orderfrom some dealers in fine and precious metals.One such source is Hagstoz&Son,709 Sampson St.,Philadelphia,PA 19106,who can supply the plates in 5.1.1 inseveral thicknesses.There are other similar sources.The plates in 5.1.2 can beobtained by purchasing the brass pl
